I need to give my users a possibility to arrange contacts into different lists. For example "People we want to invite to our party". When I started to use this software, I thought that it would be possible to do with tags, but all of sudden it appeared that tags are not available within shared address books.
And as far as I understand it's not possible to do with multiple folders for single contacts. This thing is not allowed as well.

And here is a question: is it really impossble to create this kind of list with Zimbra? Or there is a solution for this problem?